It is already a landmark, but the arrival of the 'Birdman of the Rotunda' has ensured the Birmingham city centre icon is getting even more public attention than usual.
In a bizarre but eyecatching display, a giant bird's nest has appeared at 130ft on the side of the building.
And Belgian artist Benjamin Verdonck is spending this week in the structure which measures just 9ft by 9ft.
The swallow's nest, created from straw, twigs and mud, was erected on the side of the 260ft Rotunda as part of the Fierce festival, which receives more than £75,000 in public grants, including £10,000 from the city council.
A review of grants for arts organisations, ordered by city councillor John Alden following controversial publicly funded events in the past, is due to be completed in September.
Coun Alden (Con Harborne), cabinet member for leisure, sport and culture, said: "Projects such as Benjamin Verdonck's do raise eyebrows and people will begin to wonder if money is being spent on the right things. What we do not want to do is unnecessarily censor the arts and prevent people from expressing themselves freely.
"It is difficult to quantify what is value for money in the arts. What we are trying to do is make sure that the money we are spending is being spent effectively.
"There is massive support for the City of Birmingham Symphony Orchestra and Birmingham Royal Ballet, but things are not so straightforward with the alternative arts."
Mark Ball, artistic director of Fierce, defended the birdman stunt.
He said: "The Great Swallow is about making theatre immediately accessible to people and the performance has been taken out of a theatre and a public space.
"Estimation of cost have been exaggerated and the whole things is costing just several thousand pounds. When you think that this performance is going to go out to thousands and thousands of people, then it really is value for money."
Mr Ball said the appearance of the swallow's nest had caused a great deal of interest in the city, with crowds of people stopping to stare. "It is a very accurate representation of a swallow's nest and the sturdy metal frame inside is surrounded by materials which the bird would use to create its own nest such as straw and bark.
"He is going to be in there 24 hours a day for seven days so he has all of the basic amenities in there and will be alone throughout the week.
"This is not a publicity stunt, this is a performance which tells the story of someone transforming into a bird."
He added: "All of the health-and-safety arrangements have been adhered to."